Conventionally, some image forming apparatuses, such as printers, are configured so as to have a recording-medium accommodating section (for example, a so-called sheet feed cassette and a sheet feed tray) for accommodating recording mediums such as sheets therein and convey the recording medium accommodated in the recording-medium accommodating section to an image forming position (a position at which an image is formed on a recording medium) Specifically, the image forming apparatuses generally has a configuration including a feeding roller for feeding the recording medium accommodated in the recording-medium accommodating section to a conveying path and a conveying roller for conveying the recording medium after correcting slant by temporarily inhibiting passage of the recording medium conveyed by the feeding roller in the conveying path.
In the configuration of some known image forming apparatuses, miniaturization and reduction in costs are achieved by driving the feeding roller and the conveying roller by a common motor.
For example, Japanese Patent Application Publication No. 2000-335758 discloses a printer in which feed rollers and a conveying roller are driven by a common motor and slant correction is performed by transmitting a rotational driving force so that the conveying roller may rotate in the reverse direction while the feed rollers rotate in a forward direction (a rotational direction for conveying the recording medium to the image forming position). Specifically, the printer has a first sheet supply roller (first sheet feeding roller) for feeding the sheet accommodated in a sheet feed cassette to a conveying path and a second sheet supply roller (second sheet feeding roller) for passing the sheet conveyed by the first sheet supply roller. The printer has a feed roller (conveying roller) for passing the sheet conveyed by the second sheet supply roller after slant correction. The feed roller rotates in the reverse direction in the state where the first sheet supply roller and second sheet supply roller rotatingly conveys the sheet. The rotational direction of a motor is reversed at the timing when the front end of the sheet conveyed by the second sheet supply roller is pushed onto the feed roller. Thereby, the sheet conveyed by the second sheet supply roller is conveyed after slant correction is performed by the feed roller. On the other hand, when the first sheet supply roller conveys the sheet to the second sheet supply roller, the rotational axis of the first sheet, supply roller moves upward so as to separate from the surface of the sheet accommodated in the sheet feed cassette. The second sheet supply roller is configured so as to stop its rotation when the rotational direction of the motor is switched to the reverse direction and turn to a free state. With such configuration, even when the rotational direction of the motor is switched, conveying of the sheet by the feed roller is not prevented by the first sheet supply roller and the second sheet supply roller.